DNA-binding domain of Drosophila Dorsocross and related T-box proteins
Drosophila Dorsocross (Doc) includes three Dorsocross paralogs, Doc1-3. These are key cardiogenic T-box transcription factors during specification and differentiation of heart cells. Drosophila Doc also functions in caudal visceral mesoderm development, and modulates Notch signaling in the developing Drosophila eye by regulating the expression of Delta in the eye imaginal discs. Doc also functions in the morphogenesis of epithelial tissues: in Drosophila, which possesses a single extraembryonic (EE) membrane, it is essential for EE epithelia tissue maintenance while in Tribolium castaneum, which has 2 EE membranes, Doc plays a major role in EE morphogenetic events throughout development without affecting EE tissue specificity or maintenance. This subfamily belongs to the T-box family of transcription factors which play a multitude of diverse functions throughout development. The founding member of the T-box family is Brachyury (also known as TBXT, or T). T-box family members share a conserved DNA-binding domain (T-box) which binds DNA in a sequence-specific manner. Common features shared by T-box family members are DNA-binding and transcriptional regulatory activity, a role in development, and conserved expression patterns.